The invention relates to a seat and/or backrest covering for a chair, in particular an office chair, having a frame-tensioned mesh-like fabric.
In an office chair disclosed by EP 0 856 269 A2 and having a synchronizing mechanism for adjusting the inclination of its seat/backrest unit, the seat and the backrest are covered by a mesh-like fabric. For this purpose, the mesh-like fabric is clamped in a flexible frame which, for its part, is inserted with a form fit into a peripheral groove of a load-bearing frame forming the load-bearing structure of the seat or the backrest. This type of mesh covering of the seat and/or of the backrest of a chair is very complicated in production terms.
The invention is therefore based on the object of specifying a comparatively simple type of mesh covering of the seat and/or the backrest of a chair, in particular an office chair.
According to the invention, this object is achieved by the features of claim 1. For this purpose, the mesh-like fabric is held by means of a large number of bolt-like or needle-like pins, which are arranged on the periphery of a load-bearing frame forming the load-bearing structure of the seat or the backrest. The tensioning of the mesh or of the fabric is in this case carried out either when the mesh-like fabric is fitted directly onto the pins, for example by each or every second mesh or the mesh of fabric being led over such a pin. A covering frame fitted onto the load-bearing frame on the mesh side ensures that the mesh-like fabric is held on the load-bearing frame.
Alternatively, however, the tensioning of the mesh is carried out by means of the covering frame, by the fabric which is fitted onto the load-bearing frame and whose mesh is penetrated by the pins in the manner of a penetration technique being tensioned by means of contours and mating contours provided on the covering frame, on the one hand, and on the load-bearing frame, on the other hand, when the covering frame is joined to the load-bearing frame.
The covering frame is expediently positioned and/or held on the load-bearing frame by means of a tongue-and-groove joint which runs on the frame faces, facing the mesh-like fabric, of the covering frame and of the load-bearing frame, underneath the pins, which are preferably arranged in a comb-like manner. The groove is expediently provided on the load-bearing frame and the tongue on the covering frame. As a result, by means of the tongue contour provided on the covering frame, the mesh-like fabric held by the pins arranged peripherally on the frame is drawn into the groove provided on the load-bearing frame and tensioned in the process. If this tongue-and-groove joint is used only for positioning, then the covering frame is expediently held on the load-bearing frame by means of screws or the like.
At the same time as the covering frame and the load-bearing frame are joined, the pins arranged on the latter in a single-row or multi-row configuration penetrate into a corresponding groove which is provided in the covering frame and which advantageously clamps around the pins with a form fit. As a result, uniform mesh tensioning with simultaneously secure holding of the covering frame on the load-bearing frame is ensured in a simple way. Alternatively, instead of this groove, a row of holes accommodating the pins and having a number of holes which correspond with said pins and whose number corresponds to the number of pins. In this case, all or individual pins can be provided with a head, expediently a spherical head, that latches into the hole, which is then of corresponding design, in the manner of a clip-in or snap-in connection. This provides an additional or alternative method of holding the covering frame on the load-bearing frame.
Exemplary embodiments of the invention will be explained in more detail below using a drawing, in which: